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<div class="section">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="idp78984304"></a>Owning bus names</h2></div></div></div>
<p>
Using dbus-glib, you typically call RequestName manually
to own a name, like in the following excerpt:
</p>
<div class="informalexample">
<table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td class="listing_lines" align="right"><pre>1
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<td class="listing_code"><pre class="programlisting"><span class="normal">error </span><span class="symbol">=</span><span class="normal"> <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">;</span>
<span class="normal">res </span><span class="symbol">=</span><span class="normal"> </span><span class="function">dbus_g_proxy_call</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">system_bus_proxy</span><span class="symbol">,</span>
<span class="normal"> </span><span class="string">"RequestName"</span><span class="symbol">,</span>
<span class="normal"> </span><span class="symbol">&</span><span class="normal">error</span><span class="symbol">,</span>
<span class="normal"> <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-STRING:CAPS">G_TYPE_STRING</a></span><span class="symbol">,</span><span class="normal"> NAME_TO_CLAIM</span><span class="symbol">,</span>
<span class="normal"> <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-UINT:CAPS">G_TYPE_UINT</a></span><span class="symbol">,</span><span class="normal"> DBUS_NAME_FLAG_ALLOW_REPLACEMENT</span><span class="symbol">,</span>
<span class="normal"> <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-INVALID:CAPS">G_TYPE_INVALID</a></span><span class="symbol">,</span>
<span class="normal"> <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-UINT:CAPS">G_TYPE_UINT</a></span><span class="symbol">,</span><span class="normal"> </span><span class="symbol">&</span><span class="normal">result</span><span class="symbol">,</span>
<span class="normal"> <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-INVALID:CAPS">G_TYPE_INVALID</a></span><span class="symbol">);</span>
<span class="keyword">if</span><span class="normal"> </span><span class="symbol">(!</span><span class="normal">res</span><span class="symbol">)</span>
<span class="normal"> </span><span class="cbracket">{</span>
<span class="normal"> </span><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">error </span><span class="symbol">!=</span><span class="normal"> <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">)</span>
<span class="normal"> </span><span class="cbracket">{</span>
<span class="normal"> </span><span class="function"><a href="./../glib/glib/glib-Message-Logging.html#g-warning">g_warning</a></span><span class="normal"> </span><span class="symbol">(</span><span class="string">"Failed to acquire %s: %s"</span><span class="symbol">,</span>
<span class="normal"> NAME_TO_CLAIM</span><span class="symbol">,</span><span class="normal"> error</span><span class="symbol">-></span><span class="normal">message</span><span class="symbol">);</span>
<span class="normal"> </span><span class="function"><a href="./../glib/glib/glib-Error-Reporting.html#g-error-free">g_error_free</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">error</span><span class="symbol">);</span>
<span class="normal"> </span><span class="cbracket">}</span>
<span class="normal"> </span><span class="keyword">else</span>
<span class="normal"> </span><span class="cbracket">{</span>
<span class="normal"> </span><span class="function"><a href="./../glib/glib/glib-Message-Logging.html#g-warning">g_warning</a></span><span class="normal"> </span><span class="symbol">(</span><span class="string">"Failed to acquire %s"</span><span class="symbol">,</span><span class="normal"> NAME_TO_CLAIM</span><span class="symbol">);</span>
<span class="normal"> </span><span class="cbracket">}</span>
<span class="normal"> </span><span class="keyword">goto</span><span class="normal"> out</span><span class="symbol">;</span>
<span class="normal"> </span><span class="cbracket">}</span>
<span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">result </span><span class="symbol">!=</span><span class="normal"> DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER</span><span class="symbol">)</span>
<span class="normal"> </span><span class="cbracket">{</span>
<span class="normal"> </span><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">error </span><span class="symbol">!=</span><span class="normal"> <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">)</span>
<span class="normal"> </span><span class="cbracket">{</span>
<span class="normal"> </span><span class="function"><a href="./../glib/glib/glib-Message-Logging.html#g-warning">g_warning</a></span><span class="normal"> </span><span class="symbol">(</span><span class="string">"Failed to acquire %s: %s"</span><span class="symbol">,</span>
<span class="normal"> NAME_TO_CLAIM</span><span class="symbol">,</span><span class="normal"> error</span><span class="symbol">-></span><span class="normal">message</span><span class="symbol">);</span>
<span class="normal"> </span><span class="function"><a href="./../glib/glib/glib-Error-Reporting.html#g-error-free">g_error_free</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">error</span><span class="symbol">);</span>
<span class="normal"> </span><span class="cbracket">}</span>
<span class="normal"> </span><span class="keyword">else</span>
<span class="normal"> </span><span class="cbracket">{</span>
<span class="normal"> </span><span class="function"><a href="./../glib/glib/glib-Message-Logging.html#g-warning">g_warning</a></span><span class="normal"> </span><span class="symbol">(</span><span class="string">"Failed to acquire %s"</span><span class="symbol">,</span><span class="normal"> NAME_TO_CLAIM</span><span class="symbol">);</span>
<span class="normal"> </span><span class="cbracket">}</span>
<span class="normal"> </span><span class="function">exit</span><span class="normal"> </span><span class="symbol">(</span><span class="number">1</span><span class="symbol">);</span>
<span class="normal"> </span><span class="cbracket">}</span>
<span class="function">dbus_g_proxy_add_signal</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">system_bus_proxy</span><span class="symbol">,</span><span class="normal"> </span><span class="string">"NameLost"</span><span class="symbol">,</span>
<span class="normal"> <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-STRING:CAPS">G_TYPE_STRING</a></span><span class="symbol">,</span><span class="normal"> <a href="./../gobject/gobject/gobject-Type-Information.html#G-TYPE-INVALID:CAPS">G_TYPE_INVALID</a></span><span class="symbol">);</span>
<span class="function">dbus_g_proxy_connect_signal</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">system_bus_proxy</span><span class="symbol">,</span><span class="normal"> </span><span class="string">"NameLost"</span><span class="symbol">,</span>
<span class="normal"> </span><span class="function"><a href="./../gobject/gobject/gobject-Closures.html#G-CALLBACK:CAPS">G_CALLBACK</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">on_name_lost</span><span class="symbol">),</span><span class="normal"> <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">,</span><span class="normal"> <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">);</span>
<span class="comment">/* further setup ... */</span></pre></td>
</tr>
</tbody>
</table>
</div>
<p>
</p>
<p>
While you can do things this way with GDBus too, using
<a class="link" href="GDBusProxy.html#g-dbus-proxy-call-sync" title="g_dbus_proxy_call_sync ()"><code class="function">g_dbus_proxy_call_sync()</code></a>, it is much nicer to use the high-level API
for this:
</p>
<div class="informalexample">
<table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td class="listing_lines" align="right"><pre>1
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<td class="listing_code"><pre class="programlisting"><span class="keyword">static</span><span class="normal"> </span><span class="type">void</span>
<span class="function">on_name_acquired</span><span class="normal"> </span><span class="symbol">(</span><span class="usertype">GDBusConnection</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">connection</span><span class="symbol">,</span>
<span class="normal"> </span><span class="keyword">const</span><span class="normal"> </span><span class="usertype">gchar</span><span class="normal"> </span><span class="symbol">*</span><span class="normal">name</span><span class="symbol">,</span>
<span class="normal"> </span><span class="usertype">gpointer</span><span class="normal"> user_data</span><span class="symbol">)</span>
<span class="cbracket">{</span>
<span class="normal"> </span><span class="comment">/* further setup ... */</span>
<span class="cbracket">}</span>
<span class="comment">/* ... */</span>
<span class="normal"> owner_id </span><span class="symbol">=</span><span class="normal"> </span><span class="function"><a href="gio-Owning-Bus-Names.html#g-bus-own-name">g_bus_own_name</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal"><a href="GDBusConnection.html#G-BUS-TYPE-SYSTEM:CAPS">G_BUS_TYPE_SYSTEM</a></span><span class="symbol">,</span>
<span class="normal"> NAME_TO_CLAIM</span><span class="symbol">,</span>
<span class="normal"> <a href="gio-Owning-Bus-Names.html#G-BUS-NAME-OWNER-FLAGS-ALLOW-REPLACEMENT:CAPS">G_BUS_NAME_OWNER_FLAGS_ALLOW_REPLACEMENT</a></span><span class="symbol">,</span>
<span class="normal"> on_bus_acquired</span><span class="symbol">,</span>
<span class="normal"> on_name_acquired</span><span class="symbol">,</span>
<span class="normal"> on_name_lost</span><span class="symbol">,</span>
<span class="normal"> <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">,</span>
<span class="normal"> <a href="./../glib/glib/glib-Standard-Macros.html#NULL:CAPS">NULL</a></span><span class="symbol">);</span>
<span class="normal"> </span><span class="function"><a href="./../glib/glib/glib-The-Main-Event-Loop.html#g-main-loop-run">g_main_loop_run</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">loop</span><span class="symbol">);</span>
<span class="normal"> </span><span class="function"><a href="gio-Owning-Bus-Names.html#g-bus-unown-name">g_bus_unown_name</a></span><span class="normal"> </span><span class="symbol">(</span><span class="normal">owner_id</span><span class="symbol">);</span></pre></td>
</tr>
</tbody>
</table>
</div>
<p>
Note that <a class="link" href="gio-Owning-Bus-Names.html#g-bus-own-name" title="g_bus_own_name ()"><code class="function">g_bus_own_name()</code></a> works asynchronously and requires
you to enter your mainloop to await the <code class="function">on_name_aquired()</code>
callback. Also note that in order to avoid race conditions (e.g.
when your service is activated by a method call), you have to export
your manager object <span class="emphasis"><em>before</em></span> acquiring the
name. The <code class="function">on_bus_acquired()</code> callback is the right place to do
such preparations.
</p>
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